System and Method for Plasma Cutting Sheet Metal in an Automated Coil-Line Machine

ABSTRACT

A fully automated plasma sheet metal cutter that can be integrated into a HVAC coil-line and which increases the precision of cutting, decreases the time it takes to cut a particular component sheet metal part, and offers flexibility in cutting different sized and shaped holes or openings. Further, since the system is fully automated, it eliminates the error or cost attributed to a portion of the cutting process that heretofore has been associated with a manual laborer.

CROSS REFERENCE TO RELATED APPLICATION(S)

This application claims benefit of U.S. Provisional Application Ser. No.61/756,701 filed Jan. 25, 2013 and claims benefit of U.S. ProvisionalApplication Ser. No. 61/778,596, filed Mar. 13, 2013. The entiredisclosure of both documents is herein incorporated by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This disclosure is related to the field of metal cutting machines. Morespecifically, the present disclosure relates to systems, devices,methods and processes for cutting shapes into sheet metal for ductworkas part of a coil-line manufacturing system.

2. Description of the Related Art

Ductwork is a central component of forced-air heating and coolingsystems. In building structures with forced-air heating and coolingsystems, ducts are used to distribute air throughout the structure.Stated differently, air ducts are the throughways through which treatedair from heating or conditioning equipment in forced-air systems isdistributed throughout the building structure.

Air ductwork is usually constructed out of thin metal sheets. Galvanizedmild steel is the standard and most common material used in fabricatingductwork. Generally, ductwork construction starts with cutting andforming these thin metal sheets into component subparts in amanufacturing facility, attaching an insulative material known to thoseof ordinary skill in the art to one side of the thin metal sheets (ifthe sheets are to be insulated), transporting the finished ductworkcomponent parts to the building structure, and constructing the airductwork throughways on-site at the building structure.

Currently, plasma cutting is one of the methodologies most commonlyutilized to cut the thin metal sheets into the desired component partswhen fabricating ductwork. Generally, plasma cutting is a process thatis used to cut steel and other materials of different thickness with aplasma torch. In the plasma cutting process, an inert gas (such ascompressed air) is blown at high speeds out of a nozzle. At the sametime, an electric arc is formed through the gas from the nozzle to thecutting surface, turning some of that gas into plasma. Generally, theplasma is sufficiently hot to melt the metal being cut and movessufficiently fast to blow molten metal away from the cut.

Generally, there are two main types of plasma cutting tools. As would beunderstood by those of ordinary skill in the art, an HF plasma cuttingtool uses a high-frequency, high-voltage spark to ionize the air throughthe torch head and initiate an arc. Accordingly, the torch does not needto be in contact with the raw material to be cut when starting. Theother type of plasma cutting machine, a pilot arc, uses a two cycleapproach to producing plasma, also avoiding the need for initialcontact. In the pilot arc machine, a high-voltage, low current circuitis used to initialize a very small high-intensity spark within the torchbody, thereby generating a small pocket of plasma gas which is calledthe pilot arc. The pilot arc has a return path built into the torchhead. The pilot arc will remain within itself until it ignites the mainplasma arc.

In industrial cutting settings, a plasma cutter can be utilized by hand.However it is more common for the process to be automated. In both ofthese methodologies, a cutting table is utilized. The raw material to becut with the plasma cutting machine—in the case of duct work, sheetmetal—is placed onto a machine table, a large flat surface, and locatedto stops on the table and held in place. The table is generally sized tothe size of the sheet metal used. The most ubiquitous plasma cuttingmethodology in the prior art are CNC cutting tables. In the CNC cuttingtable methodology, a computer controls the torch head, producing clean,sharp cuts in the desired programmed pattern.

Notably, during this entire process the sheet metal is held rigidly tothe table and the material used is generally a sheet of confined size.Generally, the sheet metal is not manipulated in these prior artprocesses because it adds an additional degree of complexity to thecutting process. Instead, in these processes, the sheet metal is heldstationary while the plasma cutter is manipulated on a carriage andgantry moveable in the X and Y axes. CNC plasma cutter and cuttingtables have a wide use in the HVAC industry as the cutter of choice forthe component parts of ductwork fittings (that is components that arenot simply straight) such as offsets, elbows and transitions. Plasmacutters also are commonly used to form cutouts within other ductworkstructures such as to allow for the connection of two ducts at anglesand for input and output holes.

While the utilization of plasma cutters, and CNC plasma cuttingmethodologies in particular, has increased productivity in the HVACindustry since its introduction in the early 1980s, there are stillnumerous drawbacks with both this and the manual methodology. The firstproblem is a lack of precision and improper cuts. In the manual method,the reason for this lack of precision is simply basic human error. Therealso can be over or under correcting as a user of a plasma cuttermanually attempts to follow a marked pattern. In the automated methodwhen producing full length straight ducts, the ducts generally must besmaller than the sheet it is made from in order to allow for cutting andpositioning of the cutter over the sheet. This produces a necessaryamount of waste material. Additionally, the construction of the ductworkwill require additional forming operations to be completed manually asthe cutting process can generally only take place on sheet metal whichis flat and has not been folded into the 3-dimensional duct shape.

Another problem with existing methodologies is cost. Specifically, inthe manual method, the cost of the laborer who is manipulating theplasma cutter must be included in the overhead cost for the ductwork.The cost of the laborer must also be considered in the automated methodswhere an additional manual secondary operation step (such as finalfinishing of the ductwork) must be performed.

Another problem, closely related to cost, is time. The manual process,in addition to the cost of labor, is also time intensive. Moreover, theautomated CNC plasma cutting process, while faster than the manualmethodologies, is not sufficiently fast enough for many manufacturingfacilities due, in part, to the additional final finishing steps whichare performed manually and the need to transfer parts to and from thecutting table. Notably, even the most advanced currently utilizedautomated CNC plasma cutting methodologies are not fully automated. Inmany of these systems, a user is still required to manually locatepositions required to complete the cutting.

In addition, neither of these methodologies is traditionally utilized inHVAC coil-lines. HVAC coil-lines are ubiquitous in the HVAC industryand, generally, offer a complete integration of processing metal forductwork up to the point where connection accessories are utilized inthe field to assemble the ductwork. Generally, coil-lines offer thefastest methodology for making straight ductwork, offer a more accurateductwork manufacturing process, and reduce material waste and operatingcosts while producing a superior product. Coil-lines generally comprisea standard number of pieces for cutting, bending, transporting, andotherwise manipulating the coil of material which are tied together by acontroller and conveyor belt or roller system for advancing the coilmaterial through the coil line.

Generally, when making straight ductwork on a coil-line it is common fora manufacturer to maximize cost efficiency by utilizing a lighter gaugeof metal to lower the cost of the material components of the ductwork.To compensate for the decrease in stability and strength associated withthe lower gauge metal, a reinforcement system is generally used inductwork to achieve the stability lost by utilizing the lighter gaugesheet metal.

One commonly used methodology for reinforcing ductwork is a tierod-based system. Commonly, these tie rod-based systems requiredifferent sized holes in the ductwork for bolts, tie rods and dampers ofvarying sizes to be connected. In currently utilized coil-lines, therequired holes for ductwork reinforcement systems are generally achievedthrough an automated punching methodology integrated into the coil-line.These are generally mechanical die punches which are simply dropped ontothe coil material to form a hole corresponding to the size of the diehead.

However, there are numerous problems with this methodology. First, theautomated punching methodology is generally only able to punch asingle-sized circular hole in the sheet metal with each die head. If adifferent sized hole is desired, the head of the automated punchingsystem must be switched out. This requires a stoppage of the coil-lineand a resulting loss in efficiency. To compensate for this inefficiency,one current general practice in the art is to simply punch holes thatcorrespond to the largest required hole and compensate with washers orsimilar type of devices where required. Obviously, this arrangement isless than ideal and, at these points, creates possible areas of weaknessor leakage in the ductwork.

Further, the automated punching methodology utilized in coil-linesystems is generally unable to create holes of different shapes; e.g.,square or triangular holes, or particularly large holes such as can benecessary for interconnecting duct pieces with each other. Instead, ifthese holes are desired, they currently have to be created in asecondary post coil-line step manually or through using a plasma cuttingtable methodology such as those described previously. This has obviousnegative ramifications on efficiency.

In addition, it is often common to place accessory holes or openings(e.g., an access door) or openings for branches and sub-branches inductwork. Generally, this is accomplished by cutting holes in theductwork for the door, branch or sub-branch. As this is often performedafter the duct is assembled, this step often requires manual cutting andall the attendant problems and inefficiencies.

Currently, cutting of internal structures such as large holes orcut-outs is not a step that can be achieved in the coil-line process.Further, generally odd shapes which may require curved cuts or cuts atuncommon angles can generally not be performed in the coil line as themechanical punches and guillotine cutters which are particularly usefulfor performing a large number of repeated cutting operations are unableto make any form of unique or specialized cut. Accordingly, it isgenerally performed in a secondary manual step in the shop or in thefield utilizing a plasma cutting machine or metal cutting scissors.

These later cutting stages can be restricted by the size of the tablefor the plasma cutter, as would be understood by those of ordinary skillin the art, limiting the shapes of ductwork which may be created. Again,this secondary step also increases the cost, labor and complexityassociated with manufacturing ductwork.

While straight line ductwork can be manufactured on an automated plasmacutting machine without the use of a coil-line and this methodologyprovides a mechanism in which holes and openings can be created in theductwork, as noted previously, this method of manufacturing has numerousinefficiencies. For example, this process generally only produces ablank without end treatments which can be mechanically generated quicklyand efficiently in coil line operations. Further, the finished ductworkproduct is formed in a batch as opposed to continuous process. Thus, allthe additional work that can be automated on a coil-line machine (e.g.,forming and bending, notching and shearing) must be done manually in apost-cutting step in the shop or in the field. Further, as the tablerequires a precut sheet with both dimensions dictated by the size of thetable, certain shapes and cut components may be impossible, complicated,or particularly wasteful of material to form. Accordingly, there is aneed in the art for a system and device for cutting a variety of shapesin the sheet metal that can be integrated into a coil-line.

SUMMARY OF THE INVENTION

The following is a summary of the invention, which should provide to thereader a basic understanding of some aspects of the invention. Thissummary is not intended to identify critical elements of the inventionor in any way to delineate the scope of the invention. The sole purposeof this summary is to present in simplified text some aspects of theinvention as a prelude to the more detailed description presented below.

Because of these and other problems in the art, described herein, amongother things, is a methodology of plasma cutting sheet metal in anautomated coil-line machine for cutting the sheet metal component partsof ductwork for HVAC systems.

More specifically, disclosed herein is a fully automated plasma sheetmetal cutter that can be integrated into a HVAC coil-line and whichincreases the precision of cutting, decreases the time it takes to cut aparticular component sheet metal part, and offers flexibility in cuttingdifferent sized and shaped holes or openings. Further, since this systemis fully automated, it eliminates the error or cost attributed to aportion of the cutting process that heretofore has been associated witha manual laborer.

There is disclosed herein, in an embodiment, a coil line for the cuttingof ductwork in an automated fashion, the coil line comprising: a frame;drive rolls mounted to the frame and configured to unroll a materialfrom a coil; and a cutting assembly mounted to the frame, the cuttingassembly including; a gantry arranged across the material in the coilline after it is unrolled from the coil; a table, the table arrangedbelow the material in the coil line after it is unrolled from the coil;a carriage, the carriage configured to move along the gantry only in adirection generally perpendicular to the motion of the material; and acutter, the cutter located on the carriage and configured to cut thematerial on the table; wherein, when the cutter cuts the material afterit is unrolled from the coil, the cut formed by the combination of:motion of the carriage along the gantry; and motion of the materialacross the table.

In an embodiment of the coil line, the cut is formed by motion of thecarriage in two opposing directions.

In an embodiment of the coil line, the cut is formed by motion of thecarriage in two opposing directions and the material in two opposingdirections.

In an embodiment of the coil line, the cut is formed by motion of thematerial in two opposing directions.

In an embodiment of the coil line, the material comprises a metal, suchas, but not limited to, galvanized mild steel.

In an embodiment of the coil line, the cutter comprises a plasma cutter.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 provides a side assembly view of an embodiment of an automatedcoil-line machine including a plasma cutting assembly.

FIG. 2 provides a side view of an embodiment of a cutting assembly of anautomated coil-line machine.

FIG. 3 provides a front view of the embodiment of the cutting assemblyof FIG. 2.

FIG. 4 provides a side perspective view of the embodiment of the cuttingassembly of FIG. 2.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT(S)

In certain preferred embodiments described further herein, a plasmasheet metal cutter, or other cutting tool, will be part of an automatedcoil-line machine apparatus known to those of ordinary skill in the artfor the manufacturing of air ductwork. FIG. 1 provides an embodiment ofsuch a coil line machine (100). Specifically, in the presentembodiments, in contrast to the plasma cutters of the prior art whichare stand-alone apparatuses, a fully automated cutter is integrated intoan automated coil-line machine (100) that acts within an assembly linesuch that the coil material (107) sheet metal can travel down aconveying or rolling apparatus to the cutting apparatus (7), be cut bythe cutter (203) while still on the conveying apparatus and as part ofthe coil line (100), and then continue down the conveying apparatus toreceive any further modification, alteration or construction deemednecessary for the construction of the ductwork. Accordingly, alsodescribed herein is a coil-line (100) system that integrates a cuttingapparatus (7).

Thus, the devices, as described herein, are contemplated for use, incertain embodiments, with a conveyor or roller assembly coil-line (100)system (or other similar system known to those of ordinary skill in theart) for the production of sheet ductwork. In one embodiment, thiscoil-line (100) system will generally include the following elements,arranged as depicted in FIG. 1: a frame (1), a roll straightener geardriven with beading (2) which serves to remove the coil material fromthe coil and generally form it into a continuous flat sheet; a notchingassembly (3); a shear assembly (4); an encoder bracket assembly (5); amaterial support table assembly (6); a hydraulic power unit (9); a guardencoder and bracket (10); a hood 4-roll straightener (12); a pneumaticschematic notch die shift (13); a shear guard (14); a mountplate—bulkhead fitting (21); a welt pad, power unit, front end (22); abolt pad, power unit, front end (23); a guard, leveler, front end, opside (24); a guard, leveler, front end, guide side (25); a slug chuteand notcher assembly (27)(28); a bar nut (29); and a filler platestraightener hood (30). In some embodiments it is contemplated that thecoil-line (100) will also include a punching mechanism (50) known tothose of ordinary skill in the art for punching tie rod holes of a fixedsize. However, this is not essential as the cutting apparatus (7) mayrender its function superfluous.

In an embodiment disclosed herein, the coil line (100) includes acutting apparatus (7) which is integrated into a coil-line (100). In theembodiment depicted in FIG. 1, the cutting apparatus (7) is locateddirectly in front of the hole punching mechanism (50) (which punches tierod and damper holes of a standard or predetermined size), the notchers(51) (which place end notches on the sheet metal ductwork) and the shear(52) (which cuts the ductwork into component parts via a guillotine orsimilar cut). It should the understood that the sheet metal productproduced by this coil-line (100) which integrates the cutting apparatus(7) is superior to the systems and devices of the prior art because itcreates a final sheet metal product completely cut, sheered, notched andfitted, such that little to no post-assembly line manufacture ormanipulation is required.

The cutting apparatus (7) in this integrated coil-line (100) allows forthe manufacture of finished sheet metal in an assembly line, including,for example, the cutting of different size tie rod holes withoutswitching out the hole punching mechanism (50), the cutting of accessoryholes or openings or other internal cut-outs or structures, and thecutting of specialty shapes (such as, but not limited to, corners) fromthe coil material (107). Specifically, the hole punching mechanism (50)can be set at the smallest or most common hole size with any other holesbeing cut by the cutting apparatus (7). This generally eliminates theneed for washers in the resultant ductwork. Thus, this coil-line (100)with an integrated cutting apparatus (7) allows for complete integrationof the processing of metal ductwork up to the point where connectionaccessories are used in the field to assemble the ductwork.

With this integrated coil-line (100), no manual post-cutting step isneeded to form, bend, notch and sheer the sheet metal as those steps areperformed in the same manner as in a coil line of the prior art.Furthermore, it also allows for the efficient cutting of shapes ofmultiple sizes from the coil of sheet metal (107) without therestriction of size inherent in the plasma cutting tables of the priorart. In the prior art of automated cutting machines which utilized acutting table, the shapes which could be cut into the sheet metal werelimited by the size of sheet metal which could fit onto the table. Forexample, if the table could only hold an 8′×10′ sheet, the plasma cutterwas limited to cutting shapes within these dimensions. With the plasmacutting apparatus (7) integrated into the coil-line (100), there is nolonger a restriction in cutting to the size of the sheet metal becausethe sheet metal is in a continuous coil (107). Further, the use of acontinuous coil (107) reduces waste from fixed size sheets that may notconform to part sizes reducing material use and cost.

Generally, the cutting apparatus (7) utilized in the coil-line (100)will comprise a cutter or tool (203) known to those of ordinary skill inthe art. As a preliminary matter, it is also noted that the cutting,manufacturing, configuration, systems and apparatuses described hereinwill be referred to and described generally in the manner in which thecutter (203) and the raw material sheet metal (107) is manipulatedrelative to each other. For each of the systems, processes and devicesdescribed herein, the axes of motion of the cutting head of the cutter(203) will be designated as the Y axis as shown in FIGS. 2-4. Further,the axes of motion of the sheet metal coil (107) on the coil-line (100)will be designated as the X axis as shown in FIGS. 2-4. Thus, the motionof the cutter (203) head is generally perpendicular to the motion of thecoil material (107) through the coil line (100).

In addition, it is noted that the term “cutting apparatus,” (7) as usedherein, should not be limited to only include plasma-based cuttingapparatuses. While plasma cutting is expected to be the preferredcutting method for a variety of reasons, and the cutter (203) willgenerally be a plasma cutting tool, any cutter or cutting methodologyknown to those of ordinary skill in the art which can create a precisecut in sheet metal such as, but not limited to, laser, router, and waterjet cutters is contemplated as a possible cutting apparatus (7) in thedisclosed systems, devices and methods.

In general, in the system, method and device for cutting sheet metaldescribed herein, both the cutter (203) and the raw sheet metal (107) onthe coil-line (100) will be manipulated via an automated system known tothose of ordinary skill in the art to achieve cut-out component ductworkparts of the desired dimensions. In an embodiment, this can be astandard CNC control system which is configured to operate in the coilline (100) in accordance with the methods discussed herein. In thesesystems, methods and devices, the raw sheet metal material (107) on thecoil-line (100), in certain embodiments, will generally be moved by theroll straightener gear (2) of the coil-line (100), as depicted in FIG.1.

Notably, unlike the automated CNC plasma cutting methodologies of theprior art that move the plasma torch in the X and Y axes simultaneouslyover the sheet metal using a carriage arm and circular interpolation bycomputer control while the sheet metal to be cut remains affixed to thetable and stationary, in the disclosed methodology the sheet metalmaterial (107) will be manipulated in the X axis by the coil-line (100),for example, by having the sheet metal coil rotate in both directions byallowing reversal of the drive rolls (2), and/or by having the table(311) under the sheet metal (107) grasp the metal and move it forwardand backward, while the cutter (203) will move in the Y axis usingcircular interpolation by computer control.

Thus, in these systems, methods and devices, the cutter (203) will bemanipulated and move along the Y axis (and in certain contemplatedembodiments the Z axis to allow for the tool (203) to be cleared fromthe material (107) when cutting is not needed) during the cuttingprocess. In an embodiment, the cutter (203) is actually confined to thesingle Y-axis which can both provide for a more rigid structure and canprovide for easier construction. FIGS. 2-4 provide various views of agantry (201) for the plasma cutter (203) upon which a carriage (205) canbe manipulated to move along the Y axis (in addition to the Z axis incertain contemplated embodiments). The gantry (201) can be affixed inposition over the coil material (107)on the coil line (100) with thegantry (201) being configured to stretch from one side of the coil (107)to another and with the coil (107) passing under the bottom side (211)of the gantry (201) and over the table (311) to which the gantry (201)is affixed.

In an embodiment, it is contemplated that this movement along the Y axiswill be accomplished via a carriage system (205) known to those ofordinary skill in the art where the carriage can traverse the gantry(201) in any fashion including electromechanical, pneumatic, orhydraulic motors. However, any motive mechanism known to those ofordinary skill in the art for moving a cutter (203) along a single axisis contemplated in this disclosure.

Further, in certain embodiments, it is contemplated that the cutter(203) can be manipulated in the Y axis by associated controllingsoftware. In other embodiments, it is contemplated that the cutter (203)can be manipulated in both the Y and Z axes. In any of theseembodiments, the cutter (203) will have an axis or axes of movementrelative to the raw sheet metal coil (107) on the coil-line, while thesheet metal raw coil (107) will move relative to the cutter (203)—i.e.,both the raw sheet metal material and the cutter (203) will moverelative to each other to achieve the desired cut out shape for thecomponent part of the metal ductwork being cut. In certain embodiments,a software system will control the movement of both the raw sheet metalmaterial and the cutter (203) relative to each other during a cuttingevent. It should be recognized that the cutting apparatus (7) andspecifically the gantry (201) and table (311) will generally be rigidlypositioned relative to the remaining components of the coil line (100).Further, the base (211) of the gantry (201) will often be positioned soas to be in relatively close proximity to, or even in contact with, thecoil (107) of material.

In one embodiment, the type of cut achieved by the systems, methods andprocesses disclosed herein will be a complete cut. Stated differently,in these embodiments, after a cutting event, the component ductwork partwill be completely detached and separated from the associated rawmaterial sheet metal. The complete cut need not be entirely across thecoil (107).

In another preferred embodiment, the cut achieved by the methods,systems and processes disclosed herein will be a stitched cut. In thisform of cut, the cutter (203) stitches or outlines the pattern of thedesired component part via small cuts along the ultimate primary cutline leaving small amounts of material between each cut. Thus, in thisembodiment, the outlines of the ultimate component parts are placed inthe raw sheet metal. These outlines are generally not punched out orreleased from the raw material sheet metal until it leaves the coil-line(100) or until the raw material sheet metal is transported to theultimate construction site. Thus, this methodology allows ducts withlarge cutouts internal to the walls of the duct (e.g. to connect otherduct components) to still convey through the coil line efficiently andwithout separating. Another contemplated type of cut for the systems,methods and processes disclosed herein are tie rod holes, damper holesand accessory holes of any shape (e.g., circular, oval, square,rectangular) or size. Yet another contemplated type of cut for thesystems, methods and processes disclosed herein are access holes andtap-in holes.

Generally, operation of a coil line (100) including a cutting apparatus(7) will operate as follows. The material of the coil (107) will uncoilin the same manner as is known to those of ordinary skill in the art andbe sent into the coil line (100) generally by being engaged by the driverolls (2). Initially, the coil (107) is fed into the coil line (100) andis moved through the line (100) utilizing a series of grab wheels,belts, or other structures to move the coil material (107) through thecoil line (100). Upon the coil material (107) reaching the cuttingapparatus (7), the cutter (203) will generally be positioned in a holdposition which may be spaced upward (Z-axis) or the side (Y-axis) of thecoil material (107). In the event that a standard piece of straightductwork with no additional structure is being produced, the cutter(203) will remain in the this position and the coil material (107) willpass on to be punched, folded, or otherwise manipulated as known tothose of ordinary skill.

When a piece of the coil material (107) becomes positioned just priorto, and/or under the cutting apparatus (7) which requires a specializedcut, the cutter (203) will move to position over the coil material(107). The cutter (203) will then be manipulated to cut the coilmaterial (107) as the coil material (107) moves under the gantry (201).The exact nature of the movement will depend on the shape to be cut. Forexample, if the coil material (107) is to be cut lengthwise (down thecoil) in a sine wave pattern, the cutter (203) will move in the Y-axiswhile the coil material (107) moves underneath the gantry (201) in the Xaxis. As should be apparent, in the this type of cutting arrangement,the coil (107) motion is still the same as it had been previously. Thecoil material (107) will simply be progressed along the coil line (100)in the same manner it had previously. Depending on the embodiment, itmay be necessary to slow the motion of the coil material (107) throughthe line as the cutter (203) is working, but this is generally dependenton the relative X and Y components of the cut as well as the speed ofthe cutter (203) and carriage (205).

In the event that the cutout requires a piece to be removed or anothertype of cut which requires a forward and backward movement (e.g. to cutout a circle or box), the coil line conveyor mechanism (such as driverolls (2)) will generally assist with the movement. For example, to cuta box, the cutter (203) may contact the coil material (107) and remainstationary in the Y-axis while the coil material (107) progresses afixed distance under the gantry (201) (X direction). Upon the cutter(203) reaching the point where the corner of the box is to bepositioned, the coil line (100) may halt the motion of the coil material(107) along the coil line (100). The cutter (203) may then move acrossthe coil material (107) (Y direction) while the coil material (107)remains stationary (such as by being held in place by the drive rolls(2)) cutting a line generally perpendicular to the prior cut. After thenext corner is reached, the coil line (100) may reverse the direction ofthe coil line (100) operation to return the coil material (107) back thedirection it originally came (negative X direction). During this actionthe cutter (203) may again remain stationary. Upon reaching the lastcorner, the coil line (100) may again halt and the cutter (203) maytraverse back to the position where it originally contacted the coilmaterial (107) (negative Y direction). Upon reaching the starting point,the cutter (203) may be deactivated or raised (Z direction) to stop thecutting.

At this time, the cutout has been completed. In an embodiment, the coilline (100) may then restore the former motion and continue moving thecoil material (107) through the coil line (100) (X direction). This willcommonly be the case if a stitched pattern is being cut as the cutportion will simply remain as part of the coil material and resultantproduct. Alternatively, depending on the shape, the cutout portion maybe “pushed” by other material of the coil (107) downstream of the table(311) and fall clear of the coil line (100) onto the floor or acollection bin underneath the coil line (100). Alternatively, dependingon the nature of the cut portion, the coil line (100) may resume themotion of the coil material (107) in the negative X direction and dropthe cutout part off the other (upstream) side of the table (311) andthen resume forward motion (X direction) once the cutout part isconfirmed to have cleared the coil material (107).

In the event that larger pieces are potentially to be cut by the coilline (100), e.g. a large angled piece, the coil line (100) may includespecifically added drive mechanisms, such as wheels or belts, that arepart of the table (311) and serve to move cut parts off the table (311).These may then be directed by the coil line (100) to continue throughthe coil line (100), or may be purposefully diverted from the remainingcomponents of the coil line (100) if action of those components isunnecessary.

The cutting apparatus (7) disclosed herein is an advance over the otherplasma cutting systems utilized in the art because it is fullyautomated, precise, can be used in a coil-line (100) (adding flexibilityin cutting tie-rod and accessory holes into a coil-line (100) and thecapability of cutting access and branch holes into a coil-line (100))and, importantly, accomplishes the cut with movement of both the rawcoil material (107) and the cutter (203). Notably, one of the advantagesof the fully automated plasma cutter described herein is that it allowsthe cutting of internal shapes in ductwork sheet metal during acoil-line (100) and automated manufacture. For example, in certainembodiments of the cutting apparatus (7) described herein, the cuttingapparatus (7) allows cutting of internal shapes and punch outs duringassembly of core materials—the punch outs necessary to build a branch orsub-branch “t” connection point as the ductwork is manufactured andassembled.

While the invention has been disclosed in conjunction with a descriptionof certain embodiments, including those that are currently believed tobe the preferred embodiments, the detailed description is intended to beillustrative and should not be understood to limit the scope of thepresent disclosure. As would be understood by one of ordinary skill inthe art, embodiments other than those described in detail herein areencompassed by the present invention. Modifications and variations ofthe described embodiments may be made without departing from the spiritand scope of the invention.

1. A coil line for the cutting of ductwork in an automated fashion, thecoil line comprising: a frame; drive rolls mounted to said frame andconfigured to unroll a material from a coil; and a cutting assemblymounted to said frame, the cutting assembly including; a gantry arrangedacross said material in said coil line after it is unrolled from saidcoil; a table, said table arranged below said material in said coil lineafter it is unrolled from said coil; a carriage, said carriageconfigured to move along said gantry only in a direction generallyperpendicular to the motion of said material; and a cutter, said cutterlocated on said carriage and configured to cut said material on saidtable; wherein, when said cutter cuts said material after it is unrolledfrom said coil, said cut formed by the combination of: motion of saidcarriage along said gantry; and motion of said material across saidtable.
 2. The coil line of claim 1, wherein said cut is formed by motionof said carriage in two opposing directions.
 3. The coil line of claim2, wherein said cut is formed by motion of said material in two opposingdirections.
 4. The coil line of claim 1, wherein said cut is formed bymotion of said material in two opposing directions.
 5. The coil line ofclaim 1 wherein said material comprises a metal.
 6. The coil line ofclaim 5 wherein said metal comprises galvanized mild steel.
 7. The coilline of claim 1 wherein said cutter comprises a plasma cutter.